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Coronavirus, climate change and disasters: 2020 has been a hell of a year

By Kate Doyle, Saturday September 26, 2020 - 08:57 EST
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Natural disasters and Arctic melting continue irrespective of COVID-19. - ABC

While we have all been justifiably distracted by COVID-19, the Northern Hemisphere has not been OK.

Fires in Siberia, heatwaves in Europe, record wildfires in California, flooding in Africa, many, many tropical storms, and possibly the highest temperature reliably recorded on Earth.

The Red Cross and Red Crescent has have been affected by the multiple whammies of natural disasters and coronavirus.
51.6 million people affected by floods, droughts or storms and COVID-19
2.3 million affected by fire and COVID-19
431.7 million people in vulnerable populations have had to face extreme heat and COVID-19



Fingerprints of climate change

Not all natural disasters have direct links to climate change, but as , "a clear fingerprint of human-induced climate change has been identified" on many extreme weather and climate events.

Heatwaves have the most straightforward and quickest-to-quantify links to anthropogenic climate change.

Michael Wehner from the Lawrence Berkeley National Laboratory has pulled together an attribution statement, based on previously published methods, of the 2020 California heatwave — including Death Valley reaching a ridiculous 54.4C, .

It states that climate change has caused rare California heatwaves to be 3 to 4 degrees Fahrenheit warmer than they would have been without human-induced forcing.

And the US has not been the only place hot under the collar this year.



Despite a temperature of 38C being recorded in the Arctic Circle in June, Geert Jan van Oldenborgh, a climate researcher at the Royal Netherlands Meteorological Institute, said what was more remarkable were the relatively high temperatures in northern Siberia that started in January and persisted into the summer.

He said the and the prolonged heat was made 600 times more likely as a result of human-induced climate change.

"For a large area, these were the largest factors that we've ever found for an extreme weather event," he said.



It is enough to send a chill through climate scientists like Maarten van Aalst, director of the Red Cross and Red Crescent climate centre.

"Siberia had been one of those cases that scientists had been talking about 10, 20 years ago when we were worried about melting permafrost and potential releasing of methane," Dr Aalst said.

But he said it was considered as a far-out scenario that might happen over time if we did not do enough about reducing greenhouse gases.

"This year it's happening in front of our eyes."

Meanwhile the Arctic ice continued to melt, with sea ice coverage reaching the .

And all this melting has thrown an interesting spanner into the works.

Not everything fits nicely in a box

When you start adding moisture to the mix, climate attribution gets more complicated.

A colleague of Dr Oldenborgh is looking into how fires in Siberia are likely to be affected by a warming climate — and it is not as straightforward as you might think.

Because the warming climate is melting the sea ice, there is now open water off the coast where there was once just ice.



The water evaporates far more rapidly, resulting in increased moisture that comes back down as rain.

"The extra moisture, of course, inhibits forest fires and it's not clear which one of the two terms will win — the higher temperatures or the increased moisture from the open water in the Arctic Ocean," Dr van Oldenborgh said.



He also led an attribution study into Australia's bushfires last summer that gained plenty of media attention way back in time before COVID-19.

This work is publicly available but still going through the scientific review process, which usually takes around a year.

It found the weather components of the risk of big bushfires has increased by at least 30 per cent due to anthropogenic climate change.

"We think it's probably much more than that, but because of certain technical problems, we couldn't quote anything other than a lower bound," he said.



Above-average cyclones

The trade-offs between temperature and moisture become more complex when we start looking at tropical cyclones.

Determining trends in cyclones is tricky because satellite data before the 1970s is patchy and short-duration storms over sea were likely missed.

The usual line rolled out in relation to climate change and cyclones is that we can expect there to be fewer but more intense cyclones as the world warms.

But this year has been flying in the face of that statement.



The Atlantic basin, in particular, has seen far more storms than average this year.

A different naming system is used, so rather than continue though the alphabet from season to season (like our cyclones), Atlantic storms start at A each year and go through as many of the 21 names they need (some letters are grouped — only so many names start with X).

For only the second time on record, Dr van Oldenborgh said, meteorologists had run out of names and were resorting to the Greek alphabet as a backup.



Dr Wehner said these increased numbers could be entirely a natural variation. The pattern of ocean temperatures is known to strongly control the number of tropical storms, but really we do not understand the effect of climate change on the total number of tropical storms.

"But we do know that it makes the strongest tropical cyclones stronger and more damaging," Dr Wehner said.

This is because with each degree the air warms, it can hold about 7 per cent more moisture that ends up falling as rain.

But the observations suggest the extra rain is more like double that, according to Dr van Oldenborgh.

He said he did not know for sure why and that the uncertainties were large, but the theory was that it converted the difference between the warm sea surface temperatures and the cold temperatures above into mechanical energy — it's basically a Carnot cycle for the physicists and engineers out there, or like a steam engine for the rest of us.

Add that all on top of rising sea levels.



Even amid the chaos there is hope

The Atlantic is not the only place to have been hit by flood and storms this year.

Cyclone Amphan, South Asia's strongest storm in a decade, affected 15 million people in May, killing 129 as it impacted Bangladesh, India and Sri Lanka.

Any preventable loss of life is devastating, but in a historical context, 129 deaths is astoundingly low.

In 1970, Cyclone Bhola is estimated to have taken 500,000 lives in the same region, and another storm in 1991 took 140,000 lives.



"Since then we've said that's an unacceptable loss of life," Dr van Aalst said.

"As a humanitarian organisation like the Red Cross, it's just unacceptable to keep responding to those sorts of disasters rather than to try to prevent what we know is going to come back again."

Early warnings and communications have since been put in place, along with elevated concrete structures that can protect from the wind and flooding in low-lying areas.

"Interesting also from a disaster management perspective was that at the time [Cyclone Amphan] happened, COVID was already widespread in several of the areas," Dr van Aalst said, adding that people were spread over more shelters and given PPE.

"That's generally, I would say, been a success story."



Then, of course, there is coronavirus

COVID-19 has been a real challenge for the whole world, made even harder in areas without governmental safety nets and already vulnerable populations.

Dr van Aalst said climate change could also do damage through increasing uncertainty.

If there are big swings between one year and another, it reduces the ability for people to plan and build resilience.

In East Africa, for instance, after years of drought there has been massive flooding that added to a locust outbreak.

"So you've got COVID plus extreme rainfall plus a locust outbreak, so people were hit triply hard," Dr Aalst said.



He said COVID-19 had required us to make difficult choices to be able to face a global threat.

"I think that is a reality that we will have to accept also for climate change," he said.

"It's a sad thing to say, but it's like a silver lining to the big clouds we're seeing."

In some societies, people have been able to make those difficult decisions and adjust, Dr van Aalst said.

"One question, I think, is as we recover economically also from COVID, how do we rebuild our societies greener but also more resilient in the face of the rising climate shocks?"



What's in store for Australia this summer?

As a La Nina brews across the Pacific and the waters around northern Australia warm, the chances are that we will see more cyclones than normal this season.

The bushfire outlook for spring is normal across southern Australia , where the fire season is well underway.

The official summer cyclone outlook is expected mid October and the summer bushfire outlook is scheduled for November.

It has already been a hell of a year, but there is still a long way to go in 2020.


- ABC

© ABC 2020

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